An extendable electronic stylus is described. The extendable electronic stylus has a distal end that provides an electronic input to an electronic device and a first cam with an elongated member that extends between a proximal end of the stylus and its distal end. The stylus also includes a second cam that rotates relative to the first cam when the proximal end of the stylus is pushed in a distal direction. The pushing of the proximal end of the stylus causes a surface of the second cam to contact the first cam surface. The stylus also includes a cover with a first look surface. The rotation of the second cam relative to the first cam cause a second lock surface of the second cam to abut the first lock surface, thereby locking the second cam in a fixed position relative to the first cam.